py_mini_racer._objects.JSPromiseError: JavaScript rejected promise with reason: ReferenceError: atob is not defined

[wwweww]

Steps to reproduce

I have this line of code in my JavaScript " return new Uint8Array(atob(tsv).split("").map(n => n.charCodeAt(0)))
"causing an error
async def get_xcvi():
ctx = MiniRacer()
ctx.eval(js_code)
promise = ctx.eval("new Promise((res, rej) => res(get_xct()))")
res = await promise
print(res)

Expected behavior

Tell us what should happen

Actual behavior

Traceback (most recent call last):
File "J:\code\nbBotTest\nbBotTest\moduleTest\x_spider.py", line 116, in
asyncio.run(get_xcvi())
File "C:\Program Files\Python312\Lib\asyncio\runners.py", line 194, in run
return runner.run(main)
^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\asyncio\runners.py", line 118, in run
return self._loop.run_until_complete(task)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\asyncio\base_events.py", line 687, in run_until_complete
return future.result()
^^^^^^^^^^^^^^^
File "J:\code\nbBotTest\nbBotTest\moduleTest\x_spider.py", line 81, in get_xcvi
res = await promise
^^^^^^^^^^^^^
File "J:\code\nbBotTest\nbBotTest.venv\Lib\site-packages\py_mini_racer_objects.py", line 226, in _do_await
return self._unpack_promise_results(results)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "J:\code\nbBotTest\nbBotTest.venv\Lib\site-packages\py_mini_racer_objects.py", line 262, in _unpack_promise_results
raise JSPromiseError(result)
py_mini_racer._objects.JSPromiseError: JavaScript rejected promise with reason: ReferenceError: atob is not defined
at :253:13
at a (:254:9)
at get_xct (:263:21)
at :1:31
at new Promise ()
at :1:1

System configuration

PyMiniRacer 0.12.4:

Python 312:

[bpcreech]

Hi!

atob is a web Api (defined on the window object), not a JavaScript API, so PyMiniRacer and V8 don't define it.

You could try providing your own atob through wrap_py_function, although it would need to be async (so you'd need an extra await or two in your code).

An alternative would be to contribute it to PyMiniRacer as C++ code. Or, one day, [this proposal](https://tc39.es/proposal-arraybuffer-base64/spec/#sec-uint8array.frombase64] to add Uint8Array.fromBase64() to JavaScript might eventually land and get picked up by V8!